Interesting short analysis of the notebook market. In practice things are a bit more complicated, of course ...

Ultimately, Arrandale's CPU is just plain better (it's a whole process node ahead, which is key for mobile, and the Nehalem microarchitecture is superior), but Intel has hung a dud of a GPU around its neck and has forced users who want better performance to resort to exotic system-level solutions like Optimus. This misstep has left a door open for AMD to walk right through with a saner and more conventional solution. And because AMD not only offers better graphics performance but is cheaper to boot, notebook makers (and probably users) are increasingly going to opt for the AMD mobile platform.